This invention claims priority based on JP Patent Application 2011-214265 filed on Sep. 29, 2011, the entire contents thereof being incorporated by reference into the present application.
The torque fluctuation absorbing apparatus is arranged on a path of transmission of motive power between an engine and a transmission (speed changing unit) to absorb (suppress) torque fluctuations produced between the engine and the transmission. Among the torque fluctuation absorbing apparatus of various types, there is such a one including a damper unit that absorbs torque fluctuations by way of the force of elasticity (spring force). The damper unit has a structure that includes an elastic member (a coil spring) arranged for extending in a circumferential direction between two rotating members. When the two rotating members rotate relative to each other, the coil spring compresses to absorb the torque fluctuations.
Among the torque fluctuation absorbing apparatus including such damper units, there is such an apparatus in which one of the rotating members is disposed on an outer rim or on both sides of the other rotating member, and a gap or interstice between the one and the other rotating member(s) is closed by a sealing member for sealing a space within which the coil spring is housed. For example, Patent Document 1 shows such apparatus in which leaf springs (50e, 52e of FIG. 8 of Patent Document 1) are disposed in a gap or interstice between cover disk members (14e, 16e of FIG. 8 of Patent Document 1) and a central disk member (24e of FIG. 8 of Patent Document 1). The leaf springs are configured to slidably contact with inner surfaces (the coil spring housing side surfaces) of the cover disk members. Patent Document 2 also shows an apparatus having a sealing structure similar to that of Patent Document 1.
Patent Document 1: EP2103838A
Patent Document 2: United States Patent Application 2002/0128074A